Greenland temperature response to climate forcing during the last deglaciation

Citation:
Buizert, C, Gkinis V, Severinghaus JP, He F, Lecavalier BS, Kindler P, Leuenberger M, Carlson AE, Vinther B, Masson-Delmotte V, White JWC, Liu ZY, Otto-Bliesner B, Brook EJ.  2014.  Greenland temperature response to climate forcing during the last deglaciation. Science. 345:1177-1180.

Date Published:

2014/09

Keywords:

accumulation, Antarctica, circulation, diffusion, glacial termination, ice core, polar ice, Seasonality, sensitivity, trapped air

Abstract:

Greenland ice core water isotopic composition (delta O-18) provides detailed evidence for abrupt climate changes but is by itself insufficient for quantitative reconstruction of past temperatures and their spatial patterns. We investigate Greenland temperature evolution during the last deglaciation using independent reconstructions from three ice cores and simulations with a coupled ocean-atmosphere climate model. Contrary to the traditional delta O-18 interpretation, the Younger Dryas period was 4.5 degrees +/- 2 degrees C warmer than the Oldest Dryas, due to increased carbon dioxide forcing and summer insolation. The magnitude of abrupt temperature changes is larger in central Greenland (9 degrees to 14 degrees C) than in the northwest (5 degrees to 9 degrees C), fingerprinting a North Atlantic origin. Simulated changes in temperature seasonality closely track changes in the Atlantic overturning strength and support the hypothesis that abrupt climate change is mostly a winter phenomenon.

Notes:

n/a

Website

DOI:

10.1126/science.1254961